When a vehicle moves, a low pressure area forms at the rear thereof which results in increased drag. This increased drag forces the engine of the vehicle to work harder and thus, reduces mileage. The increased drag is often aggravated by the shape of the vehicle. For example, the squared off end of a semi trailer causes far more drag than the rounded ends of a sports car.
Thus, there is a need to reduce the increased drag caused by the low pressure area created behind a moving vehicle.
There have been a number of drag reducing devices described in the art. For example, U.S. Pat. No. 5,280,990 entitled “Vehicle Drag Reduction System” which issued on Jan. 25, 1994 to Rinard describes fixed position mounted vanes to direct air to the rear of a semi-tractor trailer. Similar devices are found in U.S. Pat. No. 3,999,797 entitled “Airvane Device for Bluff Vehicles and the Like” which issued on Dec. 28, 1976 to Kirsch et al. and U.S. Pat. No. 3,960,402 entitled “Vehicle Flow Direction Vanes” which issued on Jun. 1, 1976 to Keck.
U.S. Patent Application No. US2004/0256885 entitled “Rear Spoiler With Motorized Vertical and Angle Adjustability” which published on Dec. 23, 2004 to Bui provides an adjustable rear spoiler which comprises a wing-like mechanism for trucks, has electric motor actuator transmitting rotational motion to worm gear box assembly, and has wing unit and wing mounting brackets attached to upper linkage supports to create pivotal angle adjustments.
U.S. Pat. No. 6,045,095 entitled “Vane-Airfoil Combination” which issued on Apr. 4, 2000 to Parrish, IV shows a vane-airfoil combination which comprises a rotating set of vanes located in front of the leading edge of the airfoil assembly.
WIPO Application No. WO92/19485 entitled “Vehicle Streamlining Device for Pressure Drag Reduction” which published on Nov. 12, 1992 to Eliahou discloses a device for diverting air at rear of trailer which comprises a flap for streamlining a vehicle to reduce drag. The flap is raised or lowered by actuator connected to vehicle speedometer.
U.S. Pat. No. 1,714,609 entitled “Airplane” which issued on May 25, 1928 to Massey has a dual airfoil for vehicles which comprises a pair of airfoils that provide lift and have forward and rear positions and the forward is located above the second while the second is located to the rear and lower than the first.
U.S. Pat. No. 1,913,169 entitled “Wing and Like Member for Aircraft” which issued on Jun. 6, 1933 to Martin provides a combination triple airfoil for vehicles which comprises three airfoils that provide lift and reduce drag and have staggered positions relative to one another.
U.S. Pat. No. 4,810,022 entitled “Automotive Vehicle With Adjustable Aerodynamic Accessory and Control Therefor” which issued on Mar. 7, 1989 to Takagi et al. shows an adjustable aerodynamic spoiler with controller which has spoiler settings regulated automatically by sensed driving conditions such as vehicle speed, crosswinds and the like.
None of the known prior art disclose the combination set forth herein.